In displaying reconstructed digital data from, for example, a waveform memory, digital data is converted to analog representations of the instantaneous values of signal amplitude at discrete time points at some display clock rate. Often, filters or vector generators are used to interpolate between and connect the analog values, or so-called data points. This may be true for either X (horizontal) versus Y (vertical) display systems or Y (amplitude) versus T (time) display systems. In order that linear vectors be produced so that a straight line is drawn between data points on a display device, such as a cathode-ray tube or a graphics plotter, the horizontal and vertical deflection generators must receive the respective horizontal and vertical drive signals simultaneously. That is, any timing mismatch between the horizontal and vertical drive signals at the deflection generators will produce bent vectors, the degree of non-linearity depending upon the amount of time mismatch.
Time mismatch may be caused by various delay-producing mechanisms in the horizontal and vertical signal-processing paths, and may include conventional oscilloscope delay line behavior, as well as propagation delays, differences in signal path lengths, and even delays due to component variations in the digital-to-analog signal reconstruction circuits or in the display system. Of course, the effects of such delays become more apparent and pronounced as the speed at which such data points are displayed is increased because even the slightest time mismatch will result in non-linear vectors.